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Tortora chapter 7
The Skeletal System - The Axil Skeleton
Question | Answer |
---|---|
What are the five main types of bones based on shape? | Long, short, flat, irregular, sesamoid |
Where are long bones found? | Femur, Tibia, Fibula, Humerus, Radias, Ulna, Phalanges |
Long bones consist mainly of what? | Compact Bone Tissue |
What are examples of short bones? | Carpal (except for pisiform & sesamoid), Tarsal(except for calcaneous) |
What are short bones made of? | Spongy except at surface |
Flat Bones | Plates of compact enclosing spongy, include the cranial bones that protect the brain, sternum and ribs that protect thorax, and the scapula. |
Irregular Bones | Vary in shape, including vertebra, hip bones, certain facial bone, calcaneous, and sesamoid |
Sesamoid Bones | Sesmoid bones develop in tendons or ligaments. |
Functionaly, what do sesamoid bones do? | -protects tendons from excessive wear and tear - change the direction of pull of a tendon, which improves the mechanical advantage at a joint |
Suture | An immovable fibrous joint that joins the skull bones |
What are the two major types of surface markings? | #1- Depressions and Openings #2- Processes, projections or outgrowths |
BONE SURFACE MARKINGS Depression & Openings | Allow the passage of soft tissues; such as blood vessels and nerves or form joints |
BONE SURFACE MARKINGS Processes, projections and outgrowths | Help form joints or serve as attachment points for connective tissue; such as ligaments and tendons |
How many bones are in the cranium? | There are 22 bones; 8 cranial bones & 14 facial bones |
Name the 8 cranial bones | 1. Frontal Bone 2. Parietal Bones (2) 3. Occipital Bone 4. Temporal Bones (2) 5. Ethmoid Bone (1) 6. Sphenoid Bone (1) |
Name the 14 facial bones | 1. Nasal Bones (2) 2. Maxillae Bones(2) 3. Zygomatic Bones(2) 4. Mandible Bone (1) 5. Lacrimal Bones (2) 6. Palatine Bones (2) 7. Inferior Nasal Conchae Bones (2) 8. Vomer (1) |
What are the functions of the cranial bones? | -Protect the brain -muscle attachment for jaw, neck, & facial muscles |
What are the functions of the facial bones? | -protect delicate sense organs; smell, taste, vision -support entrances to digestive & respiratory system |
How many bones are in the axil skeleton? | -80 bones -lie along longitudinal axis -skull, hyoid, vertebrae, ribs, sternum & ear ossicles |
How many bones are in the appendicular skeleton? | -126 bones -upper & lower limbs, pelvic & pectoral girdles |
Foramen | Opening; through which blood vessels, nerves, or ligaments pass |
Fossa | Shallow depression |
Sulcus | Grove; furrow along a bone surface that accomondates a blood vessel, nerve, or tendon |
Meatus | Tube-like passageway or canal |
Condyle | Large, round protuberance at the end of a bone |
Facet | Smooth flat articular surface |
Trochanter | Very large projection |
Tuberosity | Large, rounded, roughened projection |
Metopic Suture | Soon after birth the left and right sides of the frontal bone unite to form the metopic suture; usually disappears between the ages 6 & 8. |
Where are the parietal bones located? | Form the greater portion of the sides & roof of the cranial cavity |
What are the functions of the parietal bones? | -the internal surfaces contain protrussions & depressions that accomodae the blood vessels; supplying the dura matter, the superficial connective tissue covering the brain |
Where ar the temporal bones located? | Forms the inferior lateral aspects of the cranium and part of the cranial floor |
The temporal bones have many bone surface markings, what are they? | 1- Temporal Squama 2- Zygomatic Arch 3- Mandibular Fossa 4- External Auditory Meatus 5- Mastoid Proces 6- Internal Auditory Meatus 7- Styloid Process 8- Stylomastoid Foramen 9- Petrous Portion 10- Carotid Foramen 11- Jugular Foramen |
What cranial bone is the temporal squama part of and where is it located? | It is the thin, flat part of the temporal bone that forms the anterior and superior part of the temple |
What cranial bone is the zygomatic process part of and where is it located? | It is part of the temporal bones; Projectes from the inferior portion of the temporal squama and articulates (forms a joint) with the temporal process of the zygomatic bone to form the zygomatic arch |
What cranial bone is the mandibular fossa part of and where is it located? | It is part of the temporal bones; it articulates with the mandible to form the TMJ (temporomandibular joint). |
The mandibular fossa and articular tubercle articualte with the mandible to form what? | The temporomandibular joint (TMJ) |
What cranial bone is the mastoid portion part of and where is it located? | Is part of the temporal bone and is located posterior and inferior to the external auditory meatus; or ear canal which directs sound waves into the ear |
What cranial bone is the external auditory meatus part of and where is it located? | It is a curved tube in the temperol bone that leads to the middle ear |
What are mastoid air cells? | Tiny air filled compartments that are seperated from the brain by thin bony partitions; located in an adult's mastiod portion; |
What is mastoiditis? | Inflammation of the mastoid air cells caused, for example by a middle ear infection; the infection may spread to the brain |
What cranial bone is the mastoid process part of and where is it located? | It s a rounded projection of the mastiod portion of the temporal bone posterior and inferior to the external auditory meatus; it is the point of attachment for many neck muscles |
What cranial bone is the internal auditory meatus part of and where is it located? | Is an opening through the petrous portion of the temporal bone through which the facial (VII)nerve & vestibulocochlear (VIII) nerve pass |
What cranial bone is the styloid process part of and where is it located? | it projects inferiorly from the inferior surface of the temporal boneand serves as a point of attachment for muscles and ligaments of the tongue and neck |
What cranial bone is the stylomastoid foramen part of and where is it located? | It is part of the temporal bone and located between the styloid process and the mastiod process; through which the facial (VII) nerve and stylomastiod artery pass |
What cranial bone is the petrous portion part od and where is it located? | It is part of the temporal bone and is located at the floor of the cranial cavity;it is triangular and located between the sphenoid and occipital bones; houses the internal ear and middle ear; structures involved in hearing and equilibrium; it also contai |
What cranial bone is the carotid foramen part of and where is it located? | It is part of the temporal bones and is located in the petrous portion of the cranial bone; the carotid artery passes throught it |
What cranial bone is the jugular foramen part of and where is it located? | It is part of the temporal bone and is located in the petrous portion of the temporal bone, posterior to the carotid foramen and anterior to the occipital bone; a passage way for the jugular vein |
The occipital bone is located where? | Forms the posterior part and most of the base of the cranium |
The foramen magnum | Is located in the inferior part of the occipital bone |
What runs through the foramen magnum? | The medulla oblongata (inferior part of the brain) connects with the spinal cord within this foramen, and the vertebral and spinal arteries also pass through it |
Where are the occipital condyles located? | They are oval processes with convex surfaces located on either side of the foramen magnum, |
The occipital condyles articulate with depressions on the first cervical vertebra (atlas) to form what joint? | The atlanto-occipital joint, which allows you to nod your head “yes" |
The hypoglossal canal is located where? | Superior to each occipital condyle on the inferior surface of the skull |
Where is the external occipital protuberance located? | Is the most prominent midline projection on the posterior surface of the occipital bone just above the foramen magnum |
What large fibrous, elastic ligament, extends from the external occipital protuberance to the seventh cervical vertebra to help support the head? | The ligamentum nuchae |
Extending laterally from the protuberance are two curved ridges, that are areas of muscle attachment. What are they? | (1)Superior nuchal lines; (2)inferior nuchal lines |
This lies at the middle part of the base of the skull and is the keystone of the cranial floor because it articulates with all the other cranial bones, holding them together | The sphenoid bone |
The body of the sphenoid bone is located where? | Is the hollowed cubelike medial portion between the ethmoid and occipital bones |
Where is the sphenoidal sinus located? | It is located in the space inside the body of the sphenoid bone; which drains into the nasal cavity |
A bony saddle-shaped structure on the superior surface of the body of the sphenoid is called? | The sella turcica |
The anterior part of the sella turcica, which forms the horn of the saddle, is a ridge called what? | The tuberculum sellae |
The seat of the saddle is a depression, called the hypophyseal fossa, what gland is located there? | The pituitary gland |
The posterior part of the sella turcica, which forms the back of the saddle, is another ridge called what? | The dorsum sellae |
The greater and lesser wings, optic foramen,superior orbital fissures, foramen ovale, foramen rotundum, foramen spinosum,and pterygoid processess are all found on what fascial bone? | The sphenoid bone |
The pterygoid processes are attachement sites for what muscles? | Some of the muscles that move the mandible (or as our notes say; jaw muscles) |
What bone is spongelike in appearance and is located on the midline in the anterior part of the cranial floor medial to the orbits? | The ethmoid bone |
The ethmoid bone is a major superior supporting structure of what cavity? | The nasal cavity |
What part of the ethmoid bone forms the superior part of the nasal septum? The medial walls of the orbits? | The perpendicular plate of the ethmoid bone forms the superior part of the nasal septum, and the lateral masses compose most of the medial walls of the orbits |
What part of the ethmoid bone lies in the anterior floor of the cranium and forms the roof of the nasal cavity? | The cribiform plate |
What plate contains the olfactory foramina through which the olfactory nerves pass? | The cribiform plate |
What projects superiorly from the cribriform plate, is a triangular process,and serves as a point of attachment for the membranes that separate the two sides of the brain? | The crista galli |
What projects inferiorly from the cribriform plate , and forms the superior portion of the nasal septum? | The perpendicular plate |
The lateral masses of the ethmoid bone compose most of the wall between the nasal cavity and the what? | The orbits |
3 to 18 air spaces called ethmoidal cells are contained in the lateral massaes of the ethmoid bone, together these cells form what? | The ethmoidal sinuses |
The lateral masses contain two thin, scroll-shaped projections lateral to the nasal septum. These are called what? | The superior nasal concha or turbinate and the middle nasal concha |
The conchae greatly increase the vascular and mucous membrane surface area in the nasal cavity; what does this do? | It warms and moistens (humidifies) inhaled air before it passes into the lungs |
The conchae also cause inhaled air to swirl, and the result is that many inhaled particles become trapped in the mucus that lines the nasal cavity. This action of the conchae helps do what? | It cleanses inhaled air before it passes into the rest of the respiratory passageways |
Why does the superior nasal conchae increase the surface area for the sense of smell? | The superior nasal conchae are near the olfactory foramina of the cribriform plate where the sensory receptors for olfaction (smell) terminate in the mucous membrane |
What paired bones meet at the midline? | The nasal bones |
What facial bone articulates with every bone of the face except the mandible? | The maxillae |
Maxillary sinus, alveolar process, palatine process, infraoribital foramen, incisive foramen, and inferior orbital fissure are structures associated with what facial bone? | The maxillae |
The union and fusion of the maxillary bones normally is completed before birth. If this fusion fails, this condition is referred to as? | A cleft palate |
What commonly called cheekbones, form the prominences of the cheeks and part of the lateral wall and floor of each orbit; they articulate with the frontal, maxilla, sphenoid, and temporal bones? | The zygomatic bones |
They are thin, roughly resemble a fingernail in size and shape, and arethe smallest bones of the face? | The lacrimal bones |
A structure that gathers tears and passes them into the nasal cavity | The lacrimal sac; found contained in the lacrimal fossa |
Two L-shaped bones form the posterior portion of the hard palate, part of the floor and lateral wall of the nasal cavity, and a small portion of the floors of the orbits. What are they? | The palatine bones |
Two bones which are inferior to the middle nasal conchae of the ethmoid bone, are separate bones, not part of the ethmoid bone. What are they? | Inferior nasal conchae |
What conchae is involved in the sense of smell? | The superior nasal conchsa |
A roughly triangular bone that forms the inferior portion of the nasal septum | The vomer |
What is the largest, strongest facial bone and is the only movable skull bone? | The mandible |
What is the distinctive functional feature of the mandible among all the skull bones? | The mandible is the only movable skull bone, other than the auditory ossicles. |
The body, the ramus, and the angle are structures are found on what facial bone? | The mandible |
On the mandible, each ramus has a posterior condylar process that articulates with the mandibular fossa and articular tubercle of the temporal bone to form what joint? | The temporomandibular joint (TMJ) |
A vertical partition composed of bone (perpendicular plate of ethmoid GLOSSARYand vomer) and cartilage, covered with a mucous membrane, separating the nasal cavity into left and right sides | Nasal septum |
What are the three components of the nasal septum? | (1)the vomer; (2;septal cartilage; (3)the perpendicular plate of the ethmoid bone |
Damage to the septal cartilage rather than the nasal bones themselves is refered to as? Figure 7-11 Nasal septum | A broken nose |
Seven bones of the skull join to form each orbit (eye socket), which contains the eyeball and associated structures, what are they? | The three cranial bones of the orbit are the frontal, sphenoid, and ethmoid; the four facial bones are the palatine, zygomatic, lacrimal, and maxilla |
Parts of the frontal and sphenoid bones comprise what portion of the orbit? | The roof |
Parts of the zygomatic and sphenoid bones form the what of the orbit? | The lateral walls |
Parts of the maxilla, zygomatic, and palatine bones make up the what of the orbit? | The floor |
Parts of the maxilla, lacrimal, ethmoid, and sphenoid bones form the what of the orbit? | The medial walls |
The skull exhibits several unique features not seen in other bones of the body, what are they? | Sutures, paranasal sinuses, and fontanels |
Suture | An immovable fibrous joint that joins skull bones |
What are the four prominent sutres found in the skull? | (1) coronal suture; (2)sagittal suture; (3) lambdoid suture; (4) Squamous sutures |
A mucus-lined air cavity in a skull bone that communicates with the nasal cavity. | Paranasal sinuses |
Where are the paranasal sinuses are located? | In the frontal, maxillary, ethmoid, and sphenoid bones |
What are the functions of the paranasal sinuses? | The paranasal sinuses produce mucus and serve as resonating chambers for vocalization |
A mesenchyme-filled space where bone formation is not yet complete, especially between the cranial bones of an infant's skull | Fontanels |
What are the functions of frontanels? | They provide some flexibility to the fetal skull, allowing the skull to change shape as it passes through the birth canal and later permitting rapid growth of the brain during infancy |
Which fontanel is bordered by four different skull bones? | The anterolateral fontanel is bordered by four different skull bones, the frontal, parietal, temporal, and sphenoid. |
An unique component of the axial skeleton that does not articulate with any other bone is called what? | The hyoid bone |
What bone supports the tongue, providing attachment sites for muscles of the tongue, neck, and pharynx? | The hyoid bone |
What functions as a strong, flexible rod with elements that can move forward, backward, and sideways, and rotate? | The vertebral column |
In addition to enclosing and protecting the spinal cord, what else does the vertebral column do? | It supports the head, and serves as a point of attachment for the ribs, pelvic girdle, and muscles of the back and upper limbs |
Which curves of the adult vertebral column are concave (relative to the anterior side of the body)? | The thoracic and sacral curves of the vertebral column are concave relative to the anterior of the body |
Why are the curves of the vertebral column important? | (1)they increase its strength; (2)help maintain balance in the upright position; (3) absorb shocks during walking; and (4)help protect the vertebrae from fracture |
What is the normal curvature of the cervical and lumbar region? | Convex (bulging out) |
What is the normal curvature of the thoracic and sacral region? | Concave (cupping in) |
They form first during fetal development and are called primary curves, what regions are they refering to? | The thoracic and sacral regions |
They begin to form later, several months after birth and are called secondary curves, what region are they referring to? | The cervical and lumbar regions |
A pad of fibrocartilage located between the bodies of two vertebrae | Intervertebral dics |
Annulus fibrous | An outer fibrous ring consisting of fibrocartilage |
Nucleus pulposus | An inner soft, pulpy, highly elastic substance |
What are the functions of the intervertebral discs? | The discs form strong joints, permit various movements of the vertebral column, and absorb vertical shock |
What is the weight-bearing part of a vertebra called? | The Body |
What are the functions of the vertebral and intervertebral foramina? | The vertebral foramina enclose the spinal cord; the intervertebral foramina provide spaces through which spinal nerves exit the vertebral column. |
A cavity within the vertebral column formed by the vertebral foramina of all the vertebrae and containing the spinal cord. | The vertebral (spinal) canal |
Which vertebrae permit you to move your head to signify “no”? | The atlas moving on the axis permits movement of the head to signify “no" |
Which parts of thoracic vertebrae articulate with the ribs? | The facets and demifacets on the bodies of the thoracic vertebrae articulate with the heads of the ribs, and the facets on the transverse processes of these vertebrae articulate with the tubercles of the ribs |
Why are the lumbar vertebrae the largest and strongest in the vertebral column? | The lumbar vertebrae are the largest and strongest in the body because the amount of weight supported by vertebrae increases toward the inferior end of the vertebral column |
How many foramina pierce the sacrum, and what is their function? | There are four pairs of sacral foramina, for a total of eight. Each anterior sacral foramen joins a posterior sacral foramen at the intervertebral foramen. Nerves and blood vessels pass through these tunnels in the bone |
Vertebrae typically consist of what sructures? | A body, a vertebral arch, and several processes |
With which ribs does the body of the sternum articulate? | The body of the sternum articulates directly or indirectly with ribs 2–10 |
What are the functions of the thorax? | It encloses and protects the organs in the thoracic and superior abdominal cavities, provides support for the bones of the upper limbs, and plays a role in breathing |
Two short, thick processes, the pedicles, project posteriorly from the vertebral body to unite with the flat laminae to form the what? | The vertebral arch |
The vertebral arch extends posteriorly from the body of the vertebra; together, the body of the vertebra and the vertebral arch surround the spinal cord by forming the what? | The vertebral foramen |
The vertebral foramen contains what? | (1)the spinal cord; (2) adipose tissue; (3) areolar connective tissue;(4)blood vessels |
The pedicles exhibit superior and inferior indentations called what? | Vertebral notches |
When the vertebral notches are stacked on top of one another, they form an opening between adjoining vertebrae on both sides of the column called what? | In intervertebral foramen |
The intervertebral foramen, permits the passage of what? | A single spinal nerve; that passes to a specific region of the body |
What three processes serve as points of attachment for muscles? | A transverse process extends laterally on each side and a single spinous process projects posteriorly |
The vertebral foramina of cervical vertebrae are the largest in the spinal column, why? | They house the cervical enlargement of the spinal cord |
What spinous processes of the cervical vertebrae are often bifid—that is, split into two parts? | Spinous Processes C2 through C6 |
It lacks a body and a spinous process, what is it? | The first cervical vertebra inferior to the skull; the atlas is a ring of bone with anterior and posterior arches and large lateral masses |
The second cervical vertebra (C2) is called what? | The axis |
What peglike process called projects superiorly through the anterior portion of the vertebral foramen of the atlas and makes a pivot on which the atlas and head rotate | The dens or odontoid process |
The articulation formed between the anterior arch of the atlas and dens of the axis, and between their articular facets, is called what? | The atlanto-axial joint |
The typical cervical vertebra are considered what? | C3-C6 |
Its single large spinous process may be seen and felt at the base of the neck. What structure is this? | The seventh cervical vertebra (C7), called the vertebra prominens |
The thoracic vertebrae are found in the chest region and articulate with what? | The ribs |
The largest and strongest of the unfused bones in the vertebral column are? | The lumbar veretbrae |
Why are the lumbar vertebrae the largest and strongest in the vertebral column? | The lumbar vertebrae are the largest and strongest in the body because the amount of weight supported by vertebrae increases toward the inferior end of the vertebral column |
How many foramina pierce the sacrum, and what is their function? | There are four pairs of sacral foramina, for a total of eight. Each anterior sacral foramen joins a posterior sacral foramen at the intervertebral foramen. Nerves and blood vessels pass through these tunnels in the bone. |
In females, the coccyx points inferiorly, why? | To allow the passage of a baby during birth |
The 1st through 7 pairs of ribs that have costal cartilages and attach directly to the sternum are called what? | True (vertebralsternal) ribs |
There are 5 pairs of ribs that their costal cartilages either attach indirectly to the sternum or do not attach to the sternum at all, what are the called? | False ribs |
The eleventh and twelfth pairs of ribs are false ribs designated as what? | Floating (vertebral) ribs; because the costal cartilage at their anterior ends does not attach to the sternum at all |
What is the most common chest injuries that usually result from direct blows, most often from impact with a steering wheel, falls, or crushing injuries to the chest? | Rib fractures |